Plasma has diverse range of applications, especially, it is an important technology element in the process of forming thin film. High quality thin films deposition is required in the field of advanced material such as semiconductor, OLED, solar cell, LED, diamond thin film etc. and generating large area and high density plasma is the most important technique satisfying this requirement.
Sputtering technology is required for thin film formation offlexible electronic device increasing its use lately, in other words, generating high density plasma through large area and at the same time minimizing thin film damage by high-energy particle and plasma electron during thin film formation applying to flexible display, flexible lighting, flexible solar battery, flexible secondary battery etc. Furthermore, low temperature process technology is required to be available for flexible plastic substrate on low temperature by plasma depositing high quality thin film
Conventional magnetron sputtering has been the system integrated with plasma generating power and ion accelerated voltage for resolving plasma generation and acceleration of ion at the same time by applying high voltage that is higher than −500V to the target. Like this, as traditional technology integrated with ion accelerated voltage and plasma generating power on magnetron sputtering applies high voltage to the target, it cannot help generating high energy particles. If target applied voltage is decreased for minimizing the generation of high energy particles, the problem dropping deposition rate greatly will happen because either plasma can be unstable or plasma density can be lower noticeably.
In order to resolve this problem, the technology that controls plasma generating power and ion accelerated voltage each independently by separating them is needed. If plasma generating power and ion accelerated voltage can be applied by separating, it will be possible to realize it in the case of wishing high density plasma generation near the target regardless of target applied voltage level, However the technical development on large area and high density plasma generation source that satisfies such a goal is hard.
However, instead of conventional substrate heating technique, atomic scale heating technique heating thin-film surface atomic layer simultaneously during thin film depositing is needed for depositing high quality thin film on low temperature. Although it is an advantageous technique for depositing large area, high quality thin film on low temperature because neutral particle beam can heat by atom unit, high flux neutral particle beam should be generated for neutral particle beam to work its atom unit heating effect. Conventional neutral particle beam source has plasma limiter between neutralizing reflection plate and substrate, which causes a problem the limiter functions as an obstacle in neutral particle beam reaching the substrate.
For resolving the problem of existing neutral particle beam source, plasma limiter should be removed, high density plasma should be generated for resulting high flux neutral particle beam, and the interaction between plasma and substrate should be minimized, but such technology development is not easy.
Therefore, new sputtering system and high flux neutral particle beam source without plasma limiter is needed for depositing thin film requiring in manufacture field such as flexible electronic device in other words, flexible display, flexible lighting, flexible solar battery, flexible secondary battery etc. Like these systems, once large area, high density plasma source is developed suitable to the goal of new thin film, they can be easily embodied. Therefore, large area, high density plasma source development is the core technology, but it is not provided enough yet.
However, conventionally, for achieving high density plasma in a high-degree vacuum, magnetic field was formed by using permanent magnet or electromagnet and microwave was irradiated so that Electron Cyclotron Resonance (ECR) plasma was generated. But conventional technology got the problem to confine high density plasma that generated in Electron Cyclotron Resonance area on account of the structure on magnetic field. For example, in the case of forming cups field by arranging many permanent magnets leaving an interval of certain space,
plasma generated in Electron Cyclotron Resonance area formed in cups field has drift motion such as ExBdrift (E-cross-B drift), magnetic field gradient B drift, magnetic field curvature drift etc. because of the magnetic field and electric field of curve so that the problem about plasma confinement occurs as plasma especially electron gets out to the both ends of magnet with the drift trajectory divergent (open curve). And other example of conventional technology is that plasma drift motion forms discontinuous trajectory so that plasma confinement effect can be decreased because of discontinuous magnetic-field distribution even though the magnet array had been made up in order to resolve plasma confinement problem by forming cups field.
However, in the conventional technology, vacuum can be kept and at the same time microwave can be incident using dielectric window between microwave irradiating equipment and plasma. But deposition process proceeds in this plasma generating source, dielectric window was coated with deposition material so that penetration ratio of microwave dramatically decreases and plasma density can be decreased, so reliability on the process can be weakened.